This invention relates to a device which senses or detects movement of the device itself or an object on which the device is placed.
There are a number of situations where it may be desirable to detect movement of an object. One category of situations involves security or protection of an item which is of a type prone to be stolen. Some of these situations occur outdoors, such as unattended vehicles and construction materials. Some occur indoors, such as VCR's, TV sets, stereo equipment, computers and the like. In accordance with this invention, a movement sensor is placed on or attached to the item. When the item is moved, the sensor detects the movement and actuates an alarm.
Another situation where the device of this invention may be useful is in a game or entertainment device where the object of the game is to move the device from a first location to a second location without tilting the device sufficiently to energize an alarm.
Mercury filled level switches have been used as motion detectors, as shown in U.S. Pat. No. 2,041,577. The concept of providing a movement sensor that does not require spatial adjustment is found in U.S. Pat. No. 4,057,791.